Signal gain control circuit, infrared touch frame and touch equipment

Abstract

The embodiment of the utility model provides a signal gain control circuit. The signal gain control circuit comprises a control module, a plurality of infrared receivers, a gain adjustment signal output module, a first signal holding module and a signal gain adjustment module, at least two first signal input ends of the control module are respectively connected with the at least two infrared receivers; a first signal output end of the control module is connected with a first input end of the gain adjustment signal output module, and each first output end of the gain adjustment signal output module is connected with a second input end of the first signal holding module; a second output end of the first signal holding module is connected with a second signal input end of the signal gain adjusting module; each first output end of the gain adjustment signal output module is also connected with a third signal input end of the signal gain adjustment module; and at least two fourth signal input ends of the signal gain adjusting module are respectively connected with at least two infrared receivers, so that the effectiveness of touch recognition is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of infrared touch technology, and in particular to a signal gain control circuit, an infrared touch frame, and an infrared touch device. Background Art

[0002] An infrared touch frame sets a plurality of infrared transmitters and a plurality of infrared receivers on four side frames of the frame body, and then controls the infrared transmitters to emit infrared signals. The infrared receivers acquire the infrared signals to obtain corresponding received signals. Thus, the infrared touch frame determines whether a touch operation occurs according to the changes in the received signals of each infrared receiver.

[0003] Currently, most infrared touch frames adopt a one-transmitter multi-receiver scanning method, that is, when each infrared transmitter is turned on to emit an infrared signal, a plurality of infrared receivers acquire the infrared signal to obtain corresponding received signals. Since the positions and angles between each infrared receiver and the infrared transmitter are different, the signal intensity values of the received signals acquired by the plurality of infrared receivers are also different, and it is necessary to perform gain adjustment on the signal intensity values of the received signals acquired by the plurality of infrared receivers to determine the user's touch operation.

[0004] In the related art, the received signals of a plurality of infrared receivers share one gain adjustment signal for adjustment, resulting in a relatively large difference in signal intensity between the adjusted received signals, and the touch operation cannot be effectively recognized. Summary of the Utility Model

[0005] To overcome the problems existing in the related art, the present application provides a signal gain control circuit, an infrared touch frame, and an infrared touch device, which can reduce the intensity difference between the infrared signals received by each infrared receiver and improve the effectiveness of recognizing touch operations.

[0006] According to the first aspect of the embodiments of the present application, a signal gain control circuit is provided, which is applied to an infrared touch frame; the infrared touch frame includes a plurality of infrared transmitters; it includes a gain adjustment signal output module, a plurality of infrared receivers, a first signal holding module, and a signal gain adjustment module;

[0007] The control module includes a first signal output end; the gain adjustment signal output module includes an input end and a plurality of output ends; the first signal holding module includes a plurality of input ends and a plurality of output ends, and the signal gain adjustment module includes a plurality of first signal input ends, a plurality of third signal input ends, and a plurality of fourth signal input ends;

[0008] The first signal output end of the control module is connected to the first input end of the gain adjustment signal output module, and each first output end of the gain adjustment signal output module is respectively connected to a second input end of the first signal holding module; a second output end of the first signal holding module is connected to a second signal input end of the signal gain adjustment module; each first output end of the gain adjustment signal output module is also respectively connected to a third signal input end of the signal gain adjustment module; at least two fourth signal input ends of the signal gain adjustment module are respectively connected to at least two infrared receivers; the at least two infrared receivers are used for receiving infrared signals sent by a plurality of infrared transmitters.

[0009] According to the second aspect of the embodiments of the present application, an infrared touch frame is provided, including a frame body, a plurality of infrared transmitters, a plurality of infrared receivers, and the above-mentioned signal gain control circuit; the plurality of infrared transmitters and the plurality of infrared receivers are respectively arranged on the side edges of the frame body; at least two fourth signal input ends of the signal gain adjustment module are respectively connected to at least two infrared receivers.

[0010] According to the third aspect of the embodiments of the present application, an infrared touch device is provided, including a display screen and the above-mentioned infrared touch frame, and the infrared touch frame is arranged around the periphery of the display screen.

[0011] In the embodiments of the present application, the first signal output end of the control module is connected to the first input end of the gain adjustment signal output module, and each first output end of the gain adjustment signal output module is respectively connected to a second input end of the first signal holding module; a second output end of the first signal holding module is connected to a second signal input end of the signal gain adjustment module; each first output end of the gain adjustment signal output module is also respectively connected to a third signal input end of the signal gain adjustment module; at least two fourth signal input ends of the signal gain adjustment module are respectively connected to at least two of the infrared receivers. Furthermore, by controlling the gain adjustment signal output module to output gain adjustment signals respectively corresponding to each of the infrared receivers in the first part of the infrared receivers in the first time period, and after being held by the first signal holding module, output to the signal gain adjustment module; controlling the gain adjustment signal output module to directly output gain adjustment signals respectively corresponding to each of the infrared receivers in the second part of the infrared receivers to the signal gain adjustment module in the second time period, so as to perform gain adjustment on the received signals of each infrared receiver by using the gain adjustment signals respectively corresponding to each infrared receiver, so that the signal intensity values of the received signals of each infrared receiver after gain adjustment are within the target signal intensity range, reducing the signal intensity difference between the received signals of each after gain adjustment, and further improving the effectiveness of touch recognition.

[0012] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and do not limit this application.

[0013] For better understanding and implementation, the present utility model will be described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a working principle diagram of an infrared touch frame in the prior art;

[0015] Figure 2 is a working principle diagram of another infrared touch frame in the prior art;

[0016] Figure 3 is a schematic structural diagram of a signal gain control circuit shown in an embodiment of this application;

[0017] Figure 4 is a schematic structural diagram of a signal gain control circuit shown in another embodiment of this application;

[0018] Figure 5 is a schematic structural diagram of a specific circuit of a signal amplification sub-module and a first signal holding sub-module in a signal gain control circuit shown in an embodiment of this application;

[0019] Figure 6 is a schematic structural diagram of a signal gain control circuit shown in another embodiment of this application;

[0020] Figure 7 is a schematic structural diagram of a signal gain control circuit shown in another embodiment of this application;

[0021] Figure 8 is a schematic structural diagram of an infrared touch frame shown in an embodiment of this application;

[0022] Figure 9 is a schematic structural diagram of an infrared touch device shown in an embodiment of this application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings.

[0024] It should be clear that the described embodiments are only a part of the embodiments of this application, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application.

[0025] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0026] In the description of the present application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects and do not necessarily describe a specific order or sequence, nor can they be construed as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. In the present application and the appended claims, the singular forms "a", "the", and "said" are also intended to include the plural forms unless the context clearly indicates otherwise. The word "if" used herein can be interpreted as "when" or "while" or "in response to determining". In addition, in the description of the present application, unless otherwise specified, "a plurality of" means two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0027] The infrared touch frame controls the infrared transmitter to emit infrared signals by arranging a plurality of infrared transmitters and a plurality of infrared receivers on the four side frames of the frame body. The infrared receivers acquire the infrared signals and obtain corresponding received signals. Thus, the infrared touch frame determines whether a touch operation occurs according to the changes in the received signals of each infrared receiver.

[0028] In the related art, there are mainly two ways to arrange infrared transmitters and infrared receivers on the four side frames of the infrared touch frame: as Figure 1 shown, one is that the infrared transmitters and infrared receivers are respectively arranged on opposite sides of the infrared touch frame; as Figure 2 shown, the other is that the infrared transmitters and infrared receivers are arranged in a staggered manner on the same side of the infrared touch frame, where Figure 1 and Figure 2 in, the white circles represent infrared transmitters and the black circles represent infrared receivers.

[0029] Currently, most infrared touch frames adopt a one-transmitter multi-receiver scanning method, that is, when each infrared transmitter is turned on to emit infrared signals, a plurality of infrared receivers acquire the infrared signals and obtain corresponding received signals. Since the positions and angles between each infrared receiver and the infrared transmitter are different, the signal strength values of the received signals acquired by the plurality of infrared receivers will also be different. Especially when the infrared transmitters and infrared receivers are arranged in a staggered manner on the same side of the infrared touch frame, the differences in the signal strength values of the received signals acquired by the infrared receivers at different positions are extremely large.

[0030] Therefore, it is necessary to perform gain adjustment on the signal strength values of the received signals obtained by the multiple infrared receivers, so that the signal strength values of the received signals obtained by the multiple infrared receivers are adjusted to the target signal strength value. Furthermore, the infrared touch frame can determine the user's touch operation according to the actually obtained signal strength values of the received signals of each infrared receiver and the target signal strength value.

[0031] In the related art, gain adjustment is performed by setting a control module, a gain adjustment signal output module, and a signal gain adjustment module in the infrared touch frame.

[0032] Among them, the control module includes a signal output terminal; the gain adjustment signal output module includes an input terminal and a plurality of output terminals; the signal gain adjustment module includes a plurality of first signal input terminals and a plurality of second signal input terminals.

[0033] The signal output terminal of the control module is connected to the signal input terminal of the gain adjustment signal output module; each signal output terminal of the gain adjustment signal output module is respectively connected to a first signal input terminal of the signal gain adjustment module in a one-to-one correspondence, and the plurality of second signal input terminals of the signal gain adjustment module are respectively connected to the plurality of infrared receivers in a one-to-one correspondence.

[0034] The control module is used to obtain the received signals of each infrared receiver, and control the gain adjustment signal output module to output a gain adjustment signal matching the signal strength of the received signal to the signal gain adjustment module according to the signal strength of each received signal; the signal gain adjustment module receives the gain adjustment signal and performs gain adjustment on the signal strength of the received signal of the infrared receiver.

[0035] In the related art, the gain adjustment signal output module is usually an internal module structure integrated in the control module. Due to the technical limitations of the control module, the number of gain adjustment signal output modules integrated in the control module is limited, and the number of signal output terminals of the gain adjustment signal output module is also limited, while the number of received signals is much larger than the number of signal output terminals of the gain adjustment output module. Therefore, in the related art, the received signals obtained by each infrared receiver are divided into several groups, and each group shares a gain adjustment signal to achieve gain adjustment of the received signals.

[0036] The inventor found during the implementation of the present invention that: since the signal strengths of the received signals within each group are different, after sharing a gain adjustment signal for gain adjustment, the signal strength differences of the received signals after gain adjustment within each group are still relatively large, which improves the effectiveness of identifying touch operations.

[0037] Taking the example that the infrared transmitters and infrared receivers are arranged in an alternating manner on the same side of the infrared touch frame, the gain adjustment method of the related art of the present application will be described below.

[0038] As Figure 2 shown, the infrared transmitters and infrared receivers are arranged in an interleaved manner on the same side of the infrared touch frame. The infrared transmitter B emits an infrared signal, and the infrared receivers 1'-8' are synchronously turned on and acquire this infrared signal to obtain corresponding received signals a, b, c, d, e, f, g, h. Since the distances and angles from the infrared receivers 1'-8' to the infrared transmitter B are all different, the signal intensities of the received signals a, b, c, d, e, f, g, h acquired by the infrared receivers 1'-8' vary greatly.

[0039] When passing through a gain adjustment output module, and the gain adjustment output module has four signal output ports for gain adjustment, the four signal output terminals of the gain adjustment output module respectively output four different gain adjustment signals A, B, C, D. These four different gain adjustment signals A, B, C, D are respectively received by the four first signal input terminals of the signal gain adjustment module. The eight second signal input terminals of the signal gain adjustment module receive the received signals a, b, c, d, e, f, g, h sent by the infrared receivers 1'-8'. At this time, the received signals a, b, c, d, e, f, g, h are divided into four groups. The first group of received signals [a, h] share the gain adjustment signal A, the second group of received signals [b, g] share the gain adjustment signal B, the third group of received signals [c, f] share the gain adjustment signal C, and the fourth group of received signals [d, e] share the gain adjustment signal D. Although the gain adjustment signals for each group are different, the received signals within each group are still adjusted with the same gain adjustment signal. Therefore, there is still a problem that the signal intensity values of the adjusted received signals vary greatly.

[0040] To this end, the first signal output end of the control module in the embodiment of the present application is connected to the first input end of the gain adjustment signal output module, and each first output end of the gain adjustment signal output module is respectively connected to one second input end of the first signal holding module; one second output end of the first signal holding module is connected to one second signal input end of the signal gain adjustment module; each first output end of the gain adjustment signal output module is also respectively connected to one third signal input end of the signal gain adjustment module; at least two fourth signal input ends of the signal gain adjustment module are respectively connected to at least two of the infrared receivers, and then by controlling the gain adjustment signal output module to output gain adjustment signals corresponding to each of the infrared receivers in the first part of the infrared receivers respectively in the first time period, and after being held by the first signal holding module, output to the signal gain adjustment module; controlling the gain adjustment signal output module to directly output gain adjustment signals corresponding to each of the infrared receivers in the second part of the infrared receivers respectively to the signal gain adjustment module in the second time period, so as to perform gain adjustment on the received signals of each infrared receiver by using the gain adjustment signals corresponding to each infrared receiver respectively, so that the signal intensity values of the received signals of each infrared receiver after gain adjustment are within the target signal intensity range, reduce the signal intensity difference between each received signal after gain adjustment, and further improve the effectiveness of touch recognition.

[0041] Please refer to Figure 3 , which is a schematic structural diagram of the signal gain control circuit shown in the embodiment of the present application. The signal gain control circuit in the embodiment of the present application is applied to the signal gain adjustment of the infrared touch frame, and is mainly used to reduce the signal intensity difference between the received signals obtained by each infrared receiver on the infrared touch frame.

[0042] The signal gain control circuit in the embodiment of the present application is applied to an infrared touch frame; the infrared touch frame includes a plurality of infrared transmitters; the signal gain control circuit includes a control module 10, a plurality of infrared receivers 11, a gain adjustment signal output module 12, a first signal holding module 13, and a signal gain adjustment module 14.

[0043] The control module 10 includes a first signal output end; the gain adjustment signal output module 12 includes a first input end and a plurality of first output ends; the first signal holding module 13 includes a plurality of second input ends and a plurality of second output ends, and the signal gain adjustment module 14 includes a plurality of second signal input ends, a plurality of third signal input ends, and a plurality of fourth signal input ends.

[0044] The first signal output terminal of the control module 10 is connected to the first input terminal of the gain adjustment signal output module 12, and each first output terminal of the gain adjustment signal output module 12 is respectively connected to a second input terminal of the first signal holding module 13; a second output terminal of the first signal holding module 13 is connected to a second signal input terminal of the signal gain adjustment module 14; each first output terminal of the gain adjustment signal output module 12 is also respectively connected to a third signal input terminal of the signal gain adjustment module 14; at least two fourth signal input terminals of the signal gain adjustment module 14 are respectively connected to at least two infrared receivers 11; the at least two infrared receivers 11 are used to receive infrared signals sent by a plurality of infrared transmitters.

[0045] The control module 10 is used to obtain the received signals of at least two infrared receivers; the control module 10 is used to control each first output terminal of the gain adjustment signal output module 12 to output a gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 respectively in the first time period according to the received signals of the first part of the infrared receivers, and after being held by the first signal holding module 13, output it to the signal gain adjustment module 14; the control module 10 is used to control each first output terminal of the gain adjustment signal output module 12 to output a gain adjustment signal corresponding to each infrared receiver 11 in the second part of the infrared receivers 11 respectively in the second time period to the signal gain adjustment module 14 according to the received signals of the second part of the infrared receivers 11, so as to adjust the received signals of each infrared receiver 11, and make the intensity values of the received signals of each adjusted infrared receiver 11 within the target signal intensity range.

[0046] Among them, the control module 10 can be a microcontroller unit (MCU), or a logic control circuit, or a control chip.

[0047] The control module 10 is also used to control the infrared transmitter to turn on, so that the corresponding infrared receiver 11 receives synchronously.

[0048] Among them, the gain adjustment signal output module 12 can be an independent digital-to-analog converter (DAC), or a digital-to-analog converter integrated inside the control module 10, or a signal source controlled by software to output different analog signals.

[0049] Each first output terminal of the gain adjustment signal output module 12 can output different gain adjustment signals in different time periods. Taking the output of two different gain adjustment signals in two different time periods as an example, each first output terminal of the gain adjustment signal output module 12 can hold a gain adjustment signal via the first signal holding module 13 and continuously output it to the signal gain adjustment module 14 in one time period, and continuously output another gain adjustment signal to the signal gain adjustment module 14 in another time period. In the embodiment of the present application, the gain adjustment signal is an analog voltage signal.

[0050] Optionally, each first output terminal of the gain adjustment signal output module 12 corresponds to two infrared receivers 11. The control module 10 controls each first output terminal of the gain adjustment signal output module 12 to send different gain adjustment signals in the first time period and the second time period, so that each infrared receiver 11 is adjusted according to its respective different gain adjustment signals.

[0051] The gain adjustment signal corresponding to the infrared receiver 11 refers to the gain adjustment signal that matches the signal strength value of the received signal obtained by the infrared receiver 11. Matching means that after the received signals obtained by each infrared receiver 11 are gain-adjusted based on their respective gain adjustment signals, they can reach the target signal strength range. For example, using their respective gain adjustment signals, the signal strength values of the received signals obtained by each infrared receiver 11 can be adjusted to the target signal strength value.

[0052] In an optional embodiment, the gain adjustment signal corresponding to each infrared receiver 11 can be determined each time the device is powered on and initialized or when the environment changes, and then directly called during the working process.

[0053] Specifically, each time the device is powered on and initialized or when the environment changes, the control module 10 controls the infrared transmitter to emit an infrared signal. Then, the control module 10 samples the received signals of each infrared receiver 11 multiple times to obtain multiple received signals of each infrared receiver 11. For each infrared receiver 11, the average value of the signal strength values of the multiple received signals obtained by sampling is calculated to obtain the respective average signal strength value of each infrared receiver 11. According to the difference between the respective average signal strength value of each infrared receiver 11 and the set target signal strength value, the gain adjustment signal corresponding to each infrared receiver 11 is obtained. Then, in the subsequent gain adjustment process, each first output terminal of the gain adjustment signal output module 12 outputs the gain adjustment signal corresponding to each infrared receiver 11 respectively, and the signal gain adjustment module 14 performs gain adjustment on the received signals obtained in real time by each infrared receiver 11 respectively according to the gain adjustment signal corresponding to each infrared receiver 11.

[0054] In another embodiment, each time when the device is powered on and initialized or the environment changes, a corresponding initial gain adjustment signal is determined for the received signal of each infrared receiver 11. Subsequently, the control module 10 obtains the received signals of the respective infrared receivers 11 in the previous frame, and based on the received signals of the respective infrared receivers 11 and the initial gain adjustment signal, controls the gain adjustment signal output module 12 to output a gain adjustment signal corresponding to each infrared receiver 11 before obtaining the received signal of the current frame.

[0055] Specifically, each time when the device is powered on and initialized or the environment changes, for the received signal of the first frame of each infrared receiver 11, the control module 10 controls the gain adjustment signal output module 12 to output an initial gain adjustment signal to the signal gain adjustment module 14. The signal gain adjustment module 14 adjusts the gain of the received signal of the first frame according to the initial gain adjustment signal. The control module 10 obtains the signal strength value of the adjusted received signal of the first frame from the signal gain adjustment module 14. If the difference between the signal strength value of the adjusted received signal of the first frame and the set target signal strength value is not within the preset difference range, the initial gain adjustment signal is increased or decreased, and the gain adjustment signal is re-determined. According to the re-determined gain adjustment signal, the received signal of the second frame of each infrared receiver 11 is adjusted. That is to say, during the working process, according to the signal strength value of the received signal of the previous frame of each adjusted infrared receiver 11, the gain adjustment signal corresponding to the current frame is determined, and the received signal of the current frame of each infrared receiver 11 is adjusted according to the gain adjustment signal corresponding to the current frame. If the difference between the signal strength value of the adjusted received signal and the set target signal strength value is within the preset difference range, the gain adjustment of the received signal is completed. If the difference between the signal strength value of the adjusted received signal and the set target signal strength value is not within the preset difference range, the corresponding gain adjustment signal is re-determined. According to the re-determined gain adjustment signal, the received signal of the next frame of each infrared receiver 11 of the current frame is adjusted until the difference between the signal strength value of the adjusted received signal and the set target signal strength value is within the preset difference range.

[0056] In yet another embodiment, for the case where some signal gain adjustment modules 14 can receive real-time gain adjustment signals for real-time adjustment, the signal gain adjustment module 14 can use the gain adjustment signal generated for the current frame for the adjustment of the current frame.

[0057] Specifically, the control module 10 obtains the receiving signal corresponding to each infrared receiver 11 in the current frame; according to the difference between the signal strength value of the receiving signal of each infrared receiver 11 and the set target signal strength value, the gain adjustment signal corresponding to each infrared receiver 11 is obtained, and then each first output end of the gain adjustment signal output module 12 is controlled to output the gain adjustment signal corresponding to each infrared receiver 11 to the signal gain adjustment module 14, and the signal gain adjustment module 14 performs gain adjustment on the receiving signal obtained by each infrared receiver 11 in the current frame.

[0058] In one embodiment, the control module 10 is used to obtain the receiving signals of at least two infrared receivers 11 of the previous frame, and according to the receiving signals of the first part of the infrared receivers 11 of the previous frame, control each first output end of the gain adjustment signal output module 12 to output the gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 in the first time period of the previous frame, and maintain the gain adjustment signal through the first signal holding module 13 and output it to the signal gain adjustment module 14.

[0059] Regarding the situation of adjusting the gain adjustment signal in real time, since the generation and transmission of the gain adjustment signal requires time, and the signal gain adjustment module 14 that adjusts the gain of the received signal is usually a voltage-controlled adjustment circuit, the voltage-controlled adjustment circuit requires a voltage signal to be connected and a stable voltage signal to trigger the adjustment, and the access of a stable voltage signal also requires a certain amount of time. Therefore, when the signal gain adjustment module 14 obtains the receiving signal of the infrared receiver 11, the signal gain adjustment module 14 may not have received a stable gain adjustment signal. Therefore, in order to achieve accurate gain adjustment of the received signal as much as possible and real-time adjustment of the gain adjustment of the received signal as much as possible, the gain adjustment signal generated by the previous frame can be used for the adjustment of the current frame.

[0060] Specifically, the control module can obtain the receiving signal of the first part of the infrared receiver 11 in the previous frame, and according to the receiving signal of the first part of the infrared receiver 11, control each first output end of the gain adjustment signal output module to output the gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receiver 11 before obtaining the receiving signal of the current frame, and maintain the output to the signal gain adjustment module 14 through the first signal holding module, so that the signal gain adjustment module 14 adjusts the gain adjustment signal of the current frame according to the infrared signal received in the previous frame, and the adjustment accuracy is higher.

[0061] It should be understood that the signal gain adjustment module 14 in the embodiments of the present application is a voltage-controlled adjustment circuit. The voltage-controlled adjustment circuit needs to have a voltage signal input and it is a stable voltage signal to trigger the adjustment. And the input of a stable voltage signal requires a certain amount of time. Therefore, when the gain adjustment signal output module outputs the gain adjustment signals corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 to the signal gain adjustment module 14 at each first output end, the first signal holding module also holds the gain adjustment signals corresponding to each infrared receiver 11 in the first part of the infrared receivers 11. When the gain adjustment signal output module stops outputting the gain adjustment signals corresponding to each infrared receiver 11 in the first part of the infrared receivers 11, the first signal holding module continues to output the held gain adjustment signals corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 to the signal gain adjustment module 14, so that the signal gain adjustment module 14 can continuously obtain the signal gain adjustment signals, and respectively perform gain adjustment on the received signals obtained by each infrared receiver 11, so that the signal strength values of the received signals of each infrared receiver 11 are within the target signal strength range.

[0062] The control module 10 is configured to control each first output end of the gain adjustment signal output module 12 to output the gain adjustment signals corresponding to each infrared receiver 11 in the second part of the infrared receivers 11 to the signal gain adjustment module 14 in the second time period of the previous frame according to the received signals of the second part of the infrared receivers 11 in the previous frame.

[0063] Specifically, the control module can obtain the received signals of the second part of the infrared receivers 11 in the previous frame, and according to the received signals of the second part of the infrared receivers 11, control each first output end of the gain adjustment signal output module to output the gain adjustment signals corresponding to each infrared receiver 11 in the second part of the infrared receivers 11 to the signal gain adjustment module 14 before obtaining the received signals of the current frame, so that the signal gain adjustment module 14 adjusts the gain adjustment signals of the current frame according to the infrared signals received in the previous frame, and the adjustment accuracy is higher.

[0064] It should be understood that the signal gain adjustment module 14 in the embodiments of the present application is a voltage-controlled adjustment circuit. The voltage-controlled adjustment circuit requires a voltage signal to be accessed and the voltage signal needs to be stable to trigger the adjustment. Moreover, it takes a certain amount of time to access a stable voltage signal. Therefore, each first output terminal of the gain adjustment signal output module outputs the gain adjustment signal corresponding to each infrared receiver 11 in the second part of the infrared receivers 11 to the signal gain adjustment module 14, so that the signal gain adjustment module 14 can continuously obtain the gain adjustment signal and perform gain adjustment on the received signals obtained by each infrared receiver 11 respectively, so that the signal strength values of the received signals of each infrared receiver 11 are within the target signal strength range.

[0065] In an optional embodiment, the sum of the number of the first part of the infrared receivers 11 and the number of the second part of the infrared receivers 11 is equal to the number of all the infrared receivers 11 corresponding to the infrared transmitter that emits the infrared signal currently. The first part of the infrared receivers 11 may be one or more of all the infrared receivers 11 corresponding to the infrared transmitter that emits the infrared signal currently, and the second part of the infrared receivers 11 may be one or more of all the infrared receivers 11 corresponding to the infrared transmitter that emits the infrared signal currently.

[0066] Among them, the target signal strength range may be a specific target strength value or a signal strength range.

[0067] Among them, the first time period is the time period within the infrared transmitter's off cycle, and the second time period is later than the first time period. The infrared transmitter's off cycle is the time period from when the infrared transmitter is turned off to when it is turned on.

[0068] In an optional embodiment, the first time period is the first preset time period within the infrared transmitter's off cycle, and the second time period is the second preset time period within the infrared transmitter's off cycle that is later than the first preset time period.

[0069] The infrared transmitter's on cycle is the time period from when the infrared transmitter is turned on to when it is turned off. All the gain adjustment signals need to be output to the signal gain adjustment module 14 within the infrared transmitter's off cycle and can be used to adjust the received infrared signals during the on cycle. That is to say, whether it is the gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 that is kept output by the first signal holding module during the second time period, or the gain adjustment signal corresponding to each infrared receiver 11 in the second part of the infrared receivers 11 that is directly output to the signal gain adjustment module 14 by the gain adjustment signal output module during the second time period, they all need to be kept output during the on cycle to facilitate the adjustment of the received infrared signals.

[0070] In another alternative embodiment, the first time period is a first preset time period within the infrared emitter's light-off cycle, and the second time period is a second preset time period that spans both the infrared emitter's light-off cycle and the infrared emitter's light-on cycle and is later than the first preset time period.

[0071] It should be understood that the gain adjustment signal only needs to be output before the infrared receiver 11 receives an infrared signal. Since the infrared signal received by the infrared receiver 11 is an analog signal, the infrared receiver 11 may not receive an infrared signal at the first moment of the light-on cycle. Before the infrared receiver 11 receives an infrared signal, it is possible to directly output, through the gain adjustment signal output module, the gain adjustment signal corresponding to each of the infrared receivers 11 in the second part of the infrared receivers 11 that are output to the signal gain adjustment module 14. It is not necessary to limit the output within the light-off cycle; it only needs to be output before receiving the infrared signal.

[0072] Specifically, since the signal gain adjustment module 14 performs gain adjustment in response to the gain adjustment signal and requires a stable and continuous gain adjustment signal, during the light-on cycle, the first signal holding module 13 maintains the output of the gain adjustment signal corresponding to each of the infrared receivers 11 in the first part of the infrared receivers 11, and the gain adjustment signal corresponding to each of the infrared receivers 11 in the second part of the infrared receivers 11 that is directly output to the signal gain adjustment module 14 through the gain adjustment signal output module also needs to be maintained until the signal gain adjustment module 14 obtains the received signal of the infrared receiver 11, and the received signals of the corresponding infrared receivers 11 are gain-adjusted using the maintained gain adjustment signals.

[0073] Among them, the first signal holding module 13 can be an integrated chip or a logic circuit. After outputting, from each first output terminal of the gain adjustment signal output module 12, the gain adjustment signal corresponding to each of the infrared receivers 11 in a part of the infrared receivers 11, the first signal holding module 13 continues to continuously output the gain adjustment signal corresponding to each of the infrared receivers 11 in the part of the infrared receivers 11 that it holds to the signal gain adjustment module 14.

[0074] Among them, the signal gain adjustment module 14 can be a logic circuit. Specifically, the signal gain adjustment module 14 is an Automatic Gain Control (AGC) circuit. The signal gain adjustment module 14 receives, through each first signal input terminal, the gain adjustment signal corresponding to each infrared receiver 11 in a part of the infrared receivers 11, and receives, through each third signal input terminal, the gain adjustment signal corresponding to each infrared receiver 11 in another part of the infrared receivers 11, and then respectively performs gain adjustment on the received signals obtained by each infrared receiver 11, so that the signal intensity values of the received signals of each infrared receiver 11 are within the target signal intensity range.

[0075] Taking an example that an infrared transmitter emits an infrared signal, eight infrared receivers 11 obtain the infrared signal to obtain eight received signals, and the gain adjustment signal output module 12 has four signal output terminals to output the gain adjustment signal, and the gain adjustment signal determined by the received signal obtained by the infrared receiver 11 in the previous frame is used to perform gain adjustment on the received signal obtained by the infrared receiver 11 in the current frame, the solution of the present application will be described.

[0076] If the time period from the turn-on of the infrared transmitter in the previous frame to the turn-off of the infrared transmitter is the on-time period T0'-T0 of the infrared transmitter in the previous frame, the time period from the turn-off of the infrared transmitter in the previous frame to the turn-on of the infrared transmitter in the current frame is the off-time period T0-T2 of the infrared transmitter in the previous frame, and the time period from the turn-on of the infrared transmitter in the current frame to the turn-off of the infrared transmitter is the on-time period T2-T3 of the infrared transmitter in the current frame, where the off-time period T0-T2 of the infrared transmitter in the previous frame is further divided into the first half period T0-T1 (the first time period) of the turn-off of the infrared transmitter in the previous frame and the second half period T1-T2 (the second time period) of the turn-off of the infrared transmitter in the previous frame.

[0077] The control module 10 controls the infrared receivers 1'-8' to receive infrared signals during the lighting-on period T0'-T0 of the previous-frame infrared emitter. During the first half period T0-T1 (the first time period) when the previous-frame infrared emitter is turned off, the control module 10 obtains the received signals a, b, c, d, e, f, g, h obtained when the infrared receivers 1'-8' are turned on during the lighting-on period T0'-T0 of the previous-frame infrared emitter. The control module 10 obtains the gain adjustment signals corresponding to the infrared receivers 1'-8' according to the signal intensities of the received signals of the previous-frame infrared receivers 1'-8', which are used for gain adjustment of the signals received by the infrared receivers 1'-8' in the current frame. The control gain adjustment signal output module 12 sends the gain adjustment signals A, B, C, D corresponding to the current-frame infrared receivers 1'-4' to the first signal holding module 13 through four signal output terminals. The first signal holding module 13 outputs the gain adjustment signals A, B, C, D to the signal gain adjustment module 14, and the first signal holding module 13 holds the gain adjustment signals A, B, C, D. When the four signal output terminals of the control gain adjustment signal output module 12 no longer output the gain adjustment signals A, B, C, D, the first signal holding module 13 continuously outputs the held gain adjustment signals A, B, C, D to the signal gain adjustment module 14, so that the signal gain adjustment module 14 continuously obtains the gain adjustment signals A, B, C, D during the lighting-on period T2-T3 of the current frame.

[0078] During the second half period T1-T2 (the second time period) when the previous-frame infrared emitter is turned off, the gain adjustment signal output module 12 continuously outputs the gain adjustment signals E, F, G, H corresponding to the current-frame infrared receivers 5'-8' to the signal gain adjustment module 14 through four signal output terminals, and the signal gain adjustment module 14 continuously obtains the gain adjustment signals E, F, G, H during the lighting-on period T2-T3 of the current frame.

[0079] The control module 10 controls the infrared receivers 1'-8' to emit infrared signals during the lighting-on period T2-T3 of the current-frame infrared emitter. The signal gain adjustment module 14 obtains the received signals a', b', c', d', e', f', g', h' obtained when the infrared receivers 1'-8' are turned on during the lighting-on period T2-T3 of the current-frame infrared emitter, and respectively performs gain adjustment on the received signals a', b', c', d', e', f', g', h' according to the gain adjustment signals A, B, C, D, E, F, G, H, so that the signal intensity values of the adjusted received signals are within the target signal intensity range.

[0080] In the embodiment of the present application, the control module 10 controls each first output terminal of the gain adjustment signal output module 12 to output a gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 in the previous frame during the first time period of the previous frame according to the received signals of the first part of the infrared receivers 11 in the infrared receiver 11 of the previous frame. After being held by the first signal holding module 13, the output is sent to the signal gain adjustment module 14; and, according to the received signals of the second part of the infrared receivers 11 in the infrared receiver 11 of the previous frame, each first output terminal of the gain adjustment signal output module 12 outputs a gain adjustment signal corresponding to each infrared receiver 11 in the second part of the infrared receivers 11 to the signal gain adjustment module 14 during the second time period of the previous frame, so that the signal gain adjustment module 14 uses the gain adjustment signals corresponding to each infrared receiver 11 in the current frame determined by the light-off period of the previous frame to adjust the gain of the received signals obtained by each infrared receiver 11 in the current frame, so that the signal intensity value of the received signal of each infrared receiver 11 in the current frame is within the target signal intensity range, reducing the signal intensity difference between each received signal in the current frame after gain adjustment and improving the effectiveness of touch recognition.

[0081] In an alternative embodiment, please refer to Figure 4 , the control module 10 further includes a first control output terminal; the first signal holding module 13 further includes a controlled terminal; the first control output terminal of the control module 10 is connected to the controlled terminal of the first signal holding module 13.

[0082] In the embodiment of the present application, the first control output terminal of the control module 10 is at a high level during the first time period, the controlled terminal of the first signal holding module 13 is at a high level, and the first signal holding module 13 is turned on, so that the gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 output by the gain adjustment signal output module 12 is transmitted to the signal gain adjustment module 14 via the first signal holding module 13, and the first signal holding module 13 holds the gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11.

[0083] The first control output terminal of the control module 10 is at a low level during the second time period, the controlled terminal of the first signal holding module 13 is at a low level, and the first signal holding module 13 is turned off, so that the first signal holding module 13 continuously outputs the gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11 that it holds to the signal gain adjustment module 14.

[0084] Optionally, depending on the specific circuit structure of the first signal holding module 13, when the control terminal of the first signal holding module 13 is at a low level, the first signal holding module 13 is turned on, and when the control terminal of the first signal holding module 13 is at a high level, the first signal holding module 13 is turned off.

[0085] The control module 10 controls the first signal holding module 13 to hold and continuously output, so that the signal gain adjustment module 14 can continuously obtain the gain adjustment signals corresponding to each infrared receiver 11 in the first part of the infrared receivers 11.

[0086] In one embodiment, refer to Figure 5 , the first signal holding module 13 includes a plurality of first signal holding sub-modules 130; the control terminal of the first signal holding module 13 includes the control terminals of the respective first signal holding sub-modules 130; the respective second input terminals of the first signal holding module 13 are the input terminals of the respective first signal holding sub-modules 130; the respective second output terminals of the first signal holding module 13 are the output terminals of the respective first signal holding sub-modules 130.

[0087] Specifically, each first output terminal of the gain adjustment signal output module 12 is connected to the input terminal of a first signal holding sub-module 130, and the control terminal of each first signal holding sub-module 130 is connected to the first control output terminal of the control module 10; the output terminal of each first signal holding sub-module 130 is connected to a second signal input terminal of the signal gain adjustment module 14.

[0088] Among them, the first control output terminal of the control module 10 is at a high level in the first time period, the control terminals of the respective first signal holding sub-modules 130 are at a high level, and the respective first signal holding sub-modules 130 are turned on, so that each first output terminal of the gain adjustment signal output module 12 outputs the gain adjustment signals corresponding to each infrared receiver 11 in the first part of the infrared receivers 11, which are transmitted to the signal gain adjustment module 14 via the corresponding first signal holding sub-modules 130, and the respective first signal holding sub-modules 130 hold the corresponding gain adjustment signals.

[0089] The first control output terminal of the control module 10 is at a low level in the second time period, the control terminals of the respective first signal holding sub-modules 130 are at a low level, and the respective first signal holding sub-modules 130 are turned off, so that the respective first signal holding sub-modules 130 continuously output the held gain adjustment signals to the signal gain adjustment module 14.

[0090] Optionally, depending on the specific circuit structure of the first signal holding sub-module, when the control terminal of the first signal holding sub-module is at a low level, the first signal holding sub-module is turned on, and when the control terminal of the first signal holding sub-module is at a high level, the first signal holding sub-module is turned off.

[0091] The control module 10 controls each first signal holding sub-module to hold and continuously output, so that the signal gain adjustment module 14 can continuously obtain the gain adjustment signal corresponding to each infrared receiver 11 in the first part of the infrared receivers 11.

[0092] In one embodiment, refer to Figure 5 , the first signal holding sub-module 130 includes a first switching element K1 and a first holding capacitor C1;

[0093] The input terminal of the first switching element K1 is the input terminal of the first signal holding sub-module 130; the output terminal of the first switching element K1 is the output terminal of the first signal holding sub-module 130; the driving terminal of the first switching element K1 is the control terminal of the first signal holding sub-module 130; one end of the first holding capacitor C1 is connected to the output terminal of the first switching element K1, and the other end of the first holding capacitor C1 is connected to the ground terminal.

[0094] Among them, the first switching element K1 includes, but is not limited to, analog switches and digital switches.

[0095] Among them, the first holding capacitor C1 includes, but is not limited to, fixed capacitors and variable capacitors.

[0096] In the embodiment of the present application, when the circuit is in the sampling state, the driving terminal of the first switching element K1 is at a high level, so that the first switching element K1 is turned on and the first holding capacitor C1 is charged; when the circuit is in the holding state, the driving terminal of the first switching element K1 is at a low level, so that the first switching element K1 is turned off, so that the first gain adjustment signal is maintained at the signal level value at the moment of disconnection.

[0097] Through the first switching element K1 and the first holding capacitor C1, the first gain adjustment signal can be held for a certain period of time.

[0098] In one embodiment, refer to Figure 6 , the signal gain control circuit further includes a signal amplification module 15.

[0099] Each first output terminal of the gain adjustment signal output module 12 is connected to a second input terminal of the first signal holding module 13 via the signal amplification module 15, and each first output terminal of the gain adjustment signal output module 12 is also connected to a third signal input terminal of the signal gain adjustment module 14 via the signal amplification module 15.

[0100] Among them, the signal amplification module 15 is used to amplify the gain adjustment signals output from each output terminal of the gain adjustment signal output module 12.

[0101] In the embodiment of the present application, considering that the gain adjustment signal output module 12 requires a certain response time to stably output a gain adjustment signal of a certain magnitude. The smaller the value of the gain adjustment signal output by the gain adjustment signal output module 12, the shorter the required response time. Therefore, a signal amplification module 15 is provided between each first output terminal of the gain adjustment signal output module 12 and a second input terminal of the first signal holding module 13, and between each first output terminal of the gain adjustment signal output module 12 and a third signal input terminal of the signal gain adjustment module 14. Each first output terminal of the gain adjustment signal output module 12 only needs to output a gain adjustment signal with a smaller value, which is then amplified by the signal amplification module 15, thereby reducing the response time of the gain adjustment signal output module 12. For example, if the gain adjustment signal output module 12 outputs an analog signal of 3.3V and the required response time is 2μs, if the signal amplification module 15 amplifies the analog signal by 2 times, the gain adjustment signal output module 12 only needs to output 1.65V. After being amplified by the signal amplification module 15, an analog signal of 3.3V can be obtained, and the required response time is 1μs.

[0102] In one embodiment, please refer to Figure 5 , the signal amplification module 15 includes a plurality of signal amplification sub-modules 150. Each first output terminal of the gain adjustment signal output module 12 is connected to a second input terminal of the first signal holding module 13 via a signal amplification sub-module 150, and each first output terminal of the gain adjustment signal output module 12 is connected to a third signal input terminal of the signal gain adjustment module 14 via a signal amplification sub-module 150.

[0103] Among them, one signal amplification sub-module 150 is used to amplify the gain adjustment signal output from the corresponding output terminal in the gain adjustment signal output module 12.

[0104] Among them, when the first signal holding module 13 includes a plurality of first signal holding sub-modules 130, each first output terminal of the gain adjustment signal output module 12 is connected to an input terminal of a first signal holding sub-module 130 via a signal amplification sub-module 150, and the output terminal of each first signal holding sub-module 130 is connected to a second signal input terminal of the signal gain adjustment module 14.

[0105] In the embodiment of the present application, considering that each first output terminal of the gain adjustment signal output module 12 requires a certain response time to stably output a gain adjustment signal of a certain magnitude. The smaller the numerical value of the analog signal output by each first output terminal of the gain adjustment signal output module 12, the shorter the required response time. For this reason, a signal amplification sub-module 150 is provided between each first output terminal of the gain adjustment signal output module 12 and a second input terminal of the first signal holding module 13, and between each first output terminal of the gain adjustment signal output module 12 and a third signal input terminal of the signal gain adjustment module 14. Alternatively, a signal amplification sub-module 150 is provided between each first output terminal of the gain adjustment signal output module 12 and an input terminal of a first signal sub-holding module 130, and between each first output terminal of the gain adjustment signal output module 12 and a third signal input terminal of the signal gain adjustment module 14. Each first output terminal of the gain adjustment signal output module 12 only needs to output a gain adjustment signal with a smaller numerical value, which is then amplified by the signal amplification sub-module 150, thereby reducing the response time of the gain adjustment signal output module 12. For example, when the gain adjustment signal output module 12 outputs an analog signal of 3.3V, the required response time is 2μs. If the signal amplification sub-module 150 amplifies the analog signal by 2 times, the gain adjustment signal output module 12 only needs to output 1.65V. After being amplified by the signal amplification sub-module 150, an analog signal of 3.3V can be obtained, and the required response time is 1μs.

[0106] In one embodiment, please refer to Figure 5 , the signal amplification sub-module 150 includes an operational amplifier A1, a first resistor R1, a second resistor R2, a third resistor R3, and a filter capacitor C2;

[0107] The non-inverting input terminal of the operational amplifier A1 is connected to the output terminal of the gain adjustment signal output module 12 through the first resistor R1; the inverting input terminal of the operational amplifier A1 is connected to the ground terminal through the second resistor R2. The inverting input terminal of the operational amplifier A1 is connected to the output terminal of the operational amplifier A1 through the third resistor R3, and the inverting input terminal of the operational amplifier A1 is connected to the output terminal of the operational amplifier A1 through the filter capacitor C2; the output terminal of the operational amplifier A1 is connected to a second input terminal of the first signal holding module and a third signal input terminal of the signal gain adjustment module; the positive power supply terminal of the operational amplifier is connected to the DC power supply, and the negative power supply terminal of the operational amplifier is grounded.

[0108] In an embodiment of the present application, the third resistor R3 is connected in parallel with the filter capacitor C2 to form a low-pass filter for suppressing circuit noise. The resistance values of the third resistor R3 and the second resistor R2 determine the amplification factor of the operational amplifier A1. Specifically, by comparing and amplifying the input voltage at the inverting input terminal of the operational amplifier A1 with the input voltage at the non-inverting input terminal of the operational amplifier A1, the output terminal of the operational amplifier A1 outputs an amplified gain adjustment signal to a second input terminal of the first signal holding module and a third signal input terminal of the signal gain adjustment module 14.

[0109] Through the operational amplifier A1, the first resistor R1, the second resistor R2, the third resistor R3, and the filter capacitor C2, the gain adjustment signal output by the gain adjustment signal output sub-module 120 can be amplified by a certain multiple, reducing the response time of the gain adjustment signal output sub-module 120.

[0110] In one embodiment, please refer to Figure 7 , a second signal holding module 16 is provided in the circuit path connecting each first output terminal of the gain adjustment signal output module 12 to a third signal input terminal of the signal gain adjustment module 14; the second signal holding module 16 includes a plurality of input terminals and a plurality of output terminals;

[0111] Each first output terminal of the gain adjustment signal output module 12 is respectively connected to an input terminal of the second signal holding module 16; an output terminal of the second signal holding module 16 is connected to a third signal input terminal of the signal gain adjustment module 14;

[0112] The control module 10 is configured to control each first output terminal of the gain adjustment signal output module 12 to output a gain adjustment signal corresponding to each infrared receiver 11 in the other part of the infrared receivers 11 during a second time period according to the received signal of the other part of the infrared receivers 11, and the second signal holding module 16 holds and outputs the signal to the signal gain adjustment module 14.

[0113] Among them, the second signal holding module 16 can be an integrated chip or a logic circuit. After each first output terminal of the gain adjustment signal output module 12 outputs a gain adjustment signal corresponding to each infrared receiver 11 in the other part of the infrared receivers 11, the second signal holding module 16 continuously outputs the held gain adjustment signal corresponding to each infrared receiver 11 in the other part of the infrared receivers 11 to the signal gain adjustment module 14.

[0114] It should be understood that the signal gain adjustment module 14 in the embodiments of the present application is a voltage-controlled adjustment circuit. The voltage-controlled adjustment circuit requires a voltage signal to be connected and a stable voltage signal to trigger the adjustment. Moreover, it takes a certain amount of time to connect a stable voltage signal. Therefore, when the gain adjustment signal output module 12 outputs the gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11 to the signal gain adjustment module 14 at each first output end, the second signal holding module 16 also holds the gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11. When the gain adjustment signal output module 12 stops outputting the gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11, the second signal holding module 16 continues to output the held gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11 to the signal gain adjustment module 14, so that the signal gain adjustment module 14 can continuously obtain the signal gain adjustment signals to adjust the received signals of the infrared receivers 11.

[0115] In one embodiment, the control module 10 further includes a second control output end; the second signal holding module 16 further includes a controlled end;

[0116] The second control output end of the control module 10 is connected to the controlled end of the second signal holding module 16.

[0117] In the embodiments of the present application, the control module 10 sends a third control signal to the controlled end of the second signal holding module 16 through the second control output end; the second signal holding module 16 transmits the gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11 to the signal gain adjustment module 14 according to the third control signal, and controls the second signal holding module 16 to hold the gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11; the control module 10 sends a fourth control signal to the controlled end of the first signal holding module 13 through the second control output end, and the second signal holding module 16 transmits the held gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11 to the signal gain adjustment module 14 according to the fourth control signal.

[0118] By controlling the second signal holding module 16 to hold and send through the control signal sent by the control module 10, the signal gain adjustment module 14 can continuously obtain the gain adjustment signals corresponding to each infrared receiver 11 in the other part of the infrared receivers 11.

[0119] In an alternative embodiment, the second signal holding module 16 includes a plurality of second signal holding sub-modules; the control end of the second signal holding module 16 includes the control ends of the respective second signal holding sub-modules; the respective input ends of the second signal holding module 16 are the input ends of the respective second signal holding sub-modules; and the respective output ends of the second signal holding module 16 are the output ends of the respective second signal holding sub-modules.

[0120] Specifically, each first output end of the gain adjustment signal output module 12 is connected to the input end of a second signal holding sub-module; the control end of each second signal holding sub-module is connected to the second control output end of the control module 10; and the output end of each second signal holding sub-module is connected to a third signal input end of the signal gain adjustment module 14.

[0121] Wherein, when each second signal holding sub-module receives a third control signal sent by the control module 10 through the second control output end, each first output end of the gain adjustment signal output module 12 outputs a gain adjustment signal corresponding to each infrared receiver 11 in the other part of the infrared receivers 11, which is transmitted to the signal gain adjustment module 14 via the corresponding second signal holding sub-module, and each second signal holding sub-module holds the corresponding gain adjustment signal; when each second signal holding sub-module receives a fourth control signal sent by the control module 10 through the first control output end, each second signal holding sub-module continuously outputs the held gain adjustment signal to the signal gain adjustment module 14.

[0122] By controlling the control signal sent by the control module 10 to control each second signal holding sub-module to hold and transmit, the signal gain adjustment module 14 can continuously obtain the gain adjustment signal corresponding to each infrared receiver 11 in the other part of the infrared receivers 11.

[0123] It can be understood that the structure and control principle of the second signal holding sub-module are completely different from those of the first signal holding sub-module 130, and will not be elaborated here.

[0124] It can be understood that, according to actual needs, more small time periods can be respectively divided in the first time period and the second time period, and more signal holding modules can be set, so that an output end of the gain adjustment signal output module 12 sends different gain adjustment signals in more different time periods, to achieve the gain adjustment of the received signals in more infrared receivers 11, which will not be elaborated in this application.

[0125] In an embodiment, please refer to Figure 8, the present application further provides an infrared touch frame 10, which includes a frame body, a plurality of infrared transmitters 110, and the above-mentioned signal gain control circuit 200; the plurality of infrared transmitters 110 and a plurality of infrared receivers 11 in the signal gain control circuit 200 are respectively arranged on the side of the frame body; at least two fourth signal input ends of the signal gain adjustment module 14 are respectively connected to at least two infrared receivers.

[0126] In the embodiment of the present application, each infrared transmitter 110 emits an infrared signal, and the corresponding plurality of infrared receivers 11 receive the infrared signal. Since the angles and distances between each infrared receiver 11 and the same infrared transmitter 110 are different, when receiving the infrared signal emitted by the same infrared transmitter 110, there will be a signal intensity difference in the received signals of the infrared receivers 11. The signal gain adjustment module 14 can perform gain adjustment on the received signals of each infrared receiver 11 according to the gain adjustment signal corresponding to the received signal, so that the signal intensities of the received signals of each adjusted infrared receiver 11 are basically the same.

[0127] In one embodiment, please refer to Figure 9 , the present application further provides an infrared touch device, which includes a display screen 100 and the above-mentioned infrared touch frame 10, and the infrared touch frame 10 is arranged around the periphery of the display screen 100.

[0128] Among them, the infrared touch device can be an infrared touch screen. Specifically, the infrared touch device can be an intelligent blackboard and an interactive flat panel.

[0129] In the embodiment of the present application, the structure of the infrared touch frame 10 is exactly the same as the foregoing description, and will not be elaborated here. By applying the above-mentioned signal gain control circuit to the infrared touch screen, since the intensity difference between infrared signals is reduced, the touch accuracy of the infrared touch screen can be improved.

[0130] It should also be noted that the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. Without further limitation, the element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, commodity or device including the element.

[0131] The above are only the embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A signal gain control circuit, applied to an infrared touch frame; the infrared touch frame comprises a plurality of infrared transmitters; characterized in that: It includes a control module, a plurality of infrared receivers, a gain adjustment signal output module, a first signal holding module and a signal gain adjustment module; The control module includes a first signal output terminal; the gain adjustment signal output module includes a first input terminal and a plurality of first output terminals; the first signal holding module includes a plurality of second input terminals and a plurality of second output terminals, and the signal gain adjustment module includes a plurality of second signal input terminals, a plurality of third signal input terminals and a plurality of fourth signal input terminals; The first signal output end of the control module is connected to the first input end of the gain adjustment signal output module, and each first output end of the gain adjustment signal output module is respectively connected to a second input end of the first signal holding module; a second output end of the first signal holding module is connected to a second signal input end of the signal gain adjustment module; each first output end of the gain adjustment signal output module is also respectively connected to a third signal input end of the signal gain adjustment module; at least two fourth signal input ends of the signal gain adjustment module are respectively connected to at least two infrared receivers; at least two infrared receivers are used to receive infrared signals sent by a number of infrared transmitters.

2. The signal gain control circuit according to claim 1, characterized in that: The control module further includes a first control output terminal; the first signal holding module further includes a controlled terminal; The first control output terminal of the control module is connected to the controlled terminal of the first signal holding module.

3. The signal gain control circuit according to claim 2, characterized in that: The first signal holding module includes several first signal holding sub-modules; the controlled end of the first signal holding module includes the controlled ends of each of the first signal holding sub-modules; each of the second input ends of the first signal holding module is the input end of each of the first signal holding sub-modules; and each of the second output ends of the first signal holding module is the output end of each of the first signal holding sub-modules.

4. The signal gain control circuit according to claim 3, characterized in that: The first signal holding submodule includes a first switch element and a first holding capacitor; The input end of the first switch element is the input end of the first signal holding submodule; the output end of the first switch element is the output end of the first signal holding submodule; the driving end of the first switch element is the controlled end of the first signal holding submodule; one end of the first holding capacitor is connected to the output end of the first switch element, and the other end of the first holding capacitor is connected to the ground.

5. The signal gain control circuit according to claim 1, characterized in that: The circuit also includes a signal amplification module; Each first output end of the gain adjustment signal output module is connected to a second input end of the first signal holding module via the signal amplification module, and each first output end of the gain adjustment signal output module is also connected to a third signal input end of the signal gain adjustment module via the signal amplification module.

6. The signal gain control circuit according to claim 5, characterized in that: The signal amplification module includes a number of signal amplification submodules; Each first output end of the gain adjustment signal output module is connected to a second input end of the first signal holding module via a signal amplifying submodule, and each first output end of the gain adjustment signal output module is connected to a third signal input end of the signal gain adjustment module via a signal amplifying submodule.

7. The signal gain control circuit according to claim 6, characterized in that: The signal amplification submodule includes an operational amplifier, a first resistor, a second resistor, a third resistor and a filter capacitor; The in-phase input terminal of the operational amplifier is connected to the output terminal of the gain adjustment signal output module via the first resistor; the inverting input terminal of the operational amplifier is connected to the ground terminal via the second resistor, the inverting input terminal of the operational amplifier is connected to the output terminal of the operational amplifier via the third resistor, and the inverting input terminal of the operational amplifier is connected to the output terminal of the operational amplifier via the filter capacitor; the output terminal of the operational amplifier is connected to a second input terminal of the first signal holding module and a third signal input terminal of the signal gain adjustment module; the positive power supply terminal of the operational amplifier is connected to a DC power supply, and the negative power supply terminal of the operational amplifier is grounded; a second signal input terminal of the signal gain adjustment module.

8. The signal gain control circuit according to claim 1, characterized in that: A second signal holding module is provided in a circuit path connecting each first output terminal of the gain adjustment signal output module and a third signal input terminal of the signal gain adjustment module; the second signal holding module includes a plurality of input terminals and a plurality of output terminals; Each first output terminal of the gain adjustment signal output module is respectively connected to an input terminal of the second signal holding module; and an output terminal of the second signal holding module is connected to a third signal input terminal of the signal gain adjustment module.

9. The signal gain control circuit according to claim 1, characterized in that: The control module is a control chip, and the gain adjustment signal output module is a digital-to-analog converter in the control chip.

10. An infrared touch frame, characterized in that: It comprises a frame, a plurality of infrared transmitters and a signal gain control circuit as described in any one of claims 1 to 9; the plurality of infrared transmitters and the plurality of infrared receivers in the signal gain control circuit are respectively arranged on the sides of the frame; and at least two fourth signal input terminals of the signal gain adjustment module are respectively connected to at least two of the infrared receivers.

11. An infrared touch device, characterized in that: It comprises a display screen and the infrared touch frame as claimed in claim 10, wherein the infrared touch frame is arranged around the display screen.

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